Work being done by ArvinMeritor, IAV (Ingenieursgesellshaft für Auto und Verkehr) and MIT on enhancing gasoline combustion with a small hydrogen gas stream is pointing toward a potential estimated improvement in gasoline fuel economy of 20% to 30%, depending upon the baseline engine.

Writing in the October issue of MTZ (Motortechnische Zeitschrift), Utz-Jens Beister from IAV and Rudy Smaling from ArvinMeritor describe their progress with the Hydrogen-Enhanced Combustion Engine (HECE) concept, as applied to an SUV-class 3.2-liter V6 test engine.

The premise of HECE, on which the research collaborative has been working for a number of years, is that the addition of a small amount of hydrogen to the cylinder charge can allow homogeneous charge ultra-lean-burn combustion engines to operate much leaner than otherwise possible.

That in itself is not a new discovery. What brings HECE closer to operational reality is the ArvinMeritor/MIT on-board, compact plasma reformer (earlier post) that can take a fraction of the conventional fuel, reform it in real-time and add the resulting hydrogen-rich gas to the remaining fuel-air mixture flowing into the engine.

In the plasma fuel reformer, air is metered into a plasma generator located upstream of a combustor. High voltage is applied to the air stream, forming high-temperature plasma. This high-temperature plasma torch flows into the combustor, initiating vigorous combustion of a rich fuel-air mixture. Within the plasma fuel reformer, partial oxidation reactions occur in the high-temperature gas phase created by the plasma, eliminating the need for a reforming catalyst.

The shift of combustion limits with hydrogen-enhanced combustion.

Adding hydrogen gas to the homogeneous fuel charge improves the ignitability of the mixture, and increases flame speed and combustion stability. In theory, the combination of a lean-burn engine with the plasma reformer could support an ultra-lean and turbocharged engine that would reduce NOx emissions to the point of not requiring aftertreatment in the exhaust stream.

Researchers at the Sloan Automotive Laboratory at MIT also discovered that both hydrogen and carbon monoxide (both products of the partial oxidation process of the reformer) act as octane enhancers. Adding the reformed fuel gas to the engine thus also supports a substantial increase in compression ratio.

Once an engine is developed that operates ultra-lean, is turbocharged—or super-charged—and is better able to withstand engine knock, engine downsizing while maintaining performance becomes a credible option that can lead to significant additional fuel economy and performance benefits.

—Beister and Smaling

Such an ultra-lean-burn, high compression-ratio, turbocharged HECE could exhibit the following characteristics:

Extremely low engine out NOx emissions requiring little or no exhaust emissions control

Comments

I have a 2007 GMC 5.4L V8. I have been researching every avenue possible and there is no end. Everyday I find something new and interesting. I have yet to find anything that will work with my vehicles coputer system (and all its wonderful components). Most systems I have run across only produce a certain amount of Hydrogen and Oxygen because the electricity is never increasesed. How hard would it be to connect the electrodes to the distributor or at least design a system that will increase ampreage with increased rpm... a system that will take readings from your O2 senseors, MAP Sensors, MAS Airflow Sensor , EFI sensors. Get it all working in unison so that your computer actually knows how much fuel to inject to match the amount of hydrogen being produced and viseversa. I am great at mechanics...not so much at electronics !

On your 07 gmc I'm assumimg 5.3l v8 I am trying some software from hp tuner it will allow me to retard timing and lean fuel at cruise. I am running 2 generators with 1 bubbler. It came from www.thehydrogas.com producing 1.8lpm They included a digital efie which I was able to control the o2's and a efie to control map voltage. Kit was complete with relays and switch and 10ga wiring. I was able to pickup almost 9mpg. Doesn't sound like alot,but I drive alot. I also adjusted iat and ect buy 10 degrees with a resister mod. Waiting for my package from www.tunertools.com to see if I can pull out more mpg.It allows you to flash the pcm . Write now I have a much smoother running truck and alot more power.

Ordered water4gas info in May 08.Made a water vaporizer with Hydrogen Peroxide. Instant milage increase on my 3.4L van. Next step made an electrolizer, installed and combined save 20-25% on my fuel mileage. I increased the mileage more by more windings in the unit feels great and I recommend it to anyone! Next stage I will add another unit and hope it works better. Jim solarenergy@rogers.com

Great invention as by using hydrogen gas it will become easy to conserve our fossil fuels which are now in row of exhaustion.This is an economical concept and will provide good benefits too.beauty products ireland